truechain

README

TrueChain Engineering Code

TrueChain is a truly fast, permissionless, secure and scalable public blockchain platform which is supported by hybrid consensus technology called Minerva and a global developer community.    TrueChain uses hybrid consensus combining PBFT and fPoW to solve the biggest problem confronting public blockchain: the contradiction between decentralization and efficiency.

TrueChain uses PBFT as fast-chain to process transactions, and leave the oversight and election of PBFT to the hands of PoW nodes. Besides, TrueChain integrates fruitchain technology into the traditional PoW protocol to become fPoW, to make the chain even more decentralized and fair.

TrueChain also creates a hybrid consensus incentive model and a stable gas fee mechanism to lower the cost for the developers and operators of DApps, and provide better infrastructure for decentralized eco-system. 

Building the source

Building getrue requires both a Go (version 1.9 or later) and a C compiler. You can install them using your favourite package manager. Once the dependencies are installed, run

make getrue

or, to build the full suite of utilities:

make all

The execuable command getrue will be found in the cmd directory.

Running getrue

Going through all the possible command line flags is out of scope here (please consult our CLI Wiki page), also you can quickly run your own getrue instance with a few common parameter combos.

Running on the Truechain main network

$ getrue console

This command will:

• Start getrue with network ID 19330 in full node mode(default, can be changed with the --syncmode flag after version 1.1).
• Start up Getrue's built-in interactive console, (via the trailing console subcommand) through which you can invoke all official web3 methods as well as Geth's own management APIs. This too is optional and if you leave it out you can always attach to an already running Getrue instance with getrue attach.

Running on the Truechain test network

To test your contracts, you can join the test network with your node.

$ getrue --testnet console

The console subcommand has the exact same meaning as above and they are equally useful on the testnet too. Please see above for their explanations if you've skipped here.

Specifying the --testnet flag, however, will reconfigure your Geth instance a bit:

• Test network uses different network ID 18928
• Instead of connecting the main TrueChain network, the client will connect to the test network, which uses testnet P2P bootnodes, and genesis states.

Configuration

As an alternative to passing the numerous flags to the getrue binary, you can also pass a configuration file via:

$ getrue --config /path/to/your_config.toml

To get an idea how the file should look like you can use the dumpconfig subcommand to export your existing configuration:

$ getrue --your-favourite-flags dumpconfig

Operating a private network

Maintaining your own private network is more involved as a lot of configurations taken for granted in the official networks need to be manually set up.

Defining the private genesis state

First, you'll need to create the genesis state of your networks, which all nodes need to be aware of and agree upon. We provide a single node JSON file at cmd/getrue/genesis_single.json:

{
  "config": {
    "chainId": 10,
    "minerva":{"durationLimit" : "0x3c",
      "minimumDifficulty":"0x7d0",
      "minimumFruitDifficulty":"0x32"
      }
  },
  "alloc":{
    "0x7c357530174275dd30e46319b89f71186256e4f7" : { "balance" : "90000000000000000000000"},
    "0x4cf807958b9f6d9fd9331397d7a89a079ef43288" : { "balance" : "90000000000000000000000"}
  },
  "committee":[
    {
      "address": "0x76ea2f3a002431fede1141b660dbb75c26ba6d97",
      "publickey": "0x04044308742b61976de7344edb8662d6d10be1c477dd46e8e4c433c1288442a79183480894107299ff7b0706490f1fb9c9b7c9e62ae62d57bd84a1e469460d8ac1"
    }
  ]
,
  "coinbase"   : "0x0000000000000000000000000000000000000000",
  "difficulty" : "0x100",
  "extraData"  : "",
  "gasLimit"   : "0x1500000",
  "nonce"      : "0x0000000000000042",
  "mixhash"    : "0x0000000000000000000000000000000000000000000000000000000000000000",
  "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000",
  "timestamp"  : "0x00"
}

With the genesis state defined in the above JSON file, you'll need to initialize every Getrue node with it prior to starting it up to ensure all blockchain parameters are correctly set:

$ getrue init path/to/genesis.json

Running a private miner

To start a getrue instance for single node, use genesis as above, and run it with these flags:

$ getrue --nodiscover --singlenode --mine --coinbase 0x8a45d70f096d3581866ed27a5017a4eeec0db2a1 --bftkeyhex "c1581e25937d9ab91421a3e1a2667c85b0397c75a195e643109938e987acecfc" --bftip "192.168.68.43" console

Which will start sending transactions periodly to this node and mining fruits and blocks.

Documentation

Index

• Variables
• type CallMsg
• type ChainReader
• type ChainStateReader
• type ChainSyncReader
• type ContractCaller
• type FilterQuery
• type GasEstimator
• type GasPricer
• type LogFilterer
• type PendingContractCaller
• type PendingStateEventer
• type PendingStateReader
• type Subscription
• type SyncProgress
• type TransactionReader
• type TransactionSender

Variables

var NotFound = errors.New("not found")

NotFound is returned by API methods if the requested item does not exist.

Types

type CallMsg

type CallMsg struct {
	From     common.Address  // the sender of the 'transaction'
	To       *common.Address // the destination contract (nil for contract creation)
	Payment  common.Address
	Gas      uint64   // if 0, the call executes with near-infinite gas
	GasPrice *big.Int // wei <-> gas exchange ratio
	Value    *big.Int // amount of wei sent along with the call
	Fee      *big.Int // amount of wei sent along with the call
	Data     []byte   // input data, usually an ABI-encoded contract method invocation
}

CallMsg contains parameters for contract calls.

type ChainReader

type ChainReader interface {
	BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error)
	BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error)
	HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error)
	HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error)
	TransactionCount(ctx context.Context, blockHash common.Hash) (uint, error)
	TransactionInBlock(ctx context.Context, blockHash common.Hash, index uint) (*types.Transaction, error)

	// This method subscribes to notifications about changes of the head block of
	// the canonical chain.
	SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (Subscription, error)
}

ChainReader provides access to the blockchain. The methods in this interface access raw data from either the canonical chain (when requesting by block number) or any blockchain fork that was previously downloaded and processed by the node. The block number argument can be nil to select the latest canonical block. Reading block headers should be preferred over full blocks whenever possible.

The returned error is NotFound if the requested item does not exist.

type ChainStateReader

type ChainStateReader interface {
	BalanceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (*big.Int, error)
	/*StorageAt(ctx context.Context, account common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error)
	CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error)*/
	NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error)
}

ChainStateReader wraps access to the state trie of the canonical blockchain. Note that implementations of the interface may be unable to return state values for old blocks. In many cases, using CallContract can be preferable to reading raw contract storage.

type ChainSyncReader

type ChainSyncReader interface {
	SyncProgress(ctx context.Context) (*SyncProgress, error)
}

ChainSyncReader wraps access to the node's current sync status. If there's no sync currently running, it returns nil.

type ContractCaller

type ContractCaller interface {
	CallContract(ctx context.Context, call CallMsg, blockNumber *big.Int) ([]byte, error)
}

A ContractCaller provides contract calls, essentially transactions that are executed by the EVM but not mined into the blockchain. ContractCall is a low-level method to execute such calls. For applications which are structured around specific contracts, the abigen tool provides a nicer, properly typed way to perform calls.

type FilterQuery

type FilterQuery struct {
	BlockHash *common.Hash     // used by eth_getLogs, return logs only from block with this hash
	FromBlock *big.Int         // beginning of the queried range, nil means genesis block
	ToBlock   *big.Int         // end of the range, nil means latest block
	Addresses []common.Address // restricts matches to events created by specific contracts

	// The Topic list restricts matches to particular event topics. Each event has a list
	// of topics. Topics matches a prefix of that list. An empty element slice matches any
	// topic. Non-empty elements represent an alternative that matches any of the
	// contained topics.
	//
	// Examples:
	// {} or nil          matches any topic list
	// {{A}}              matches topic A in first position
	// {{}, {B}}          matches any topic in first position, B in second position
	// {{A}, {B}}         matches topic A in first position, B in second position
	// {{A, B}}, {C, D}}  matches topic (A OR B) in first position, (C OR D) in second position
	Topics [][]common.Hash
}

FilterQuery contains options for contract log filtering.

type GasEstimator

type GasEstimator interface {
	EstimateGas(ctx context.Context, call CallMsg) (uint64, error)
}

GasEstimator wraps EstimateGas, which tries to estimate the gas needed to execute a specific transaction based on the pending state. There is no guarantee that this is the true gas limit requirement as other transactions may be added or removed by miners, but it should provide a basis for setting a reasonable default.

type GasPricer

type GasPricer interface {
	SuggestGasPrice(ctx context.Context) (*big.Int, error)
}

GasPricer wraps the gas price oracle, which monitors the blockchain to determine the optimal gas price given current fee market conditions.

type LogFilterer

type LogFilterer interface {
	FilterLogs(ctx context.Context, q FilterQuery) ([]types.Log, error)
	SubscribeFilterLogs(ctx context.Context, q FilterQuery, ch chan<- types.Log) (Subscription, error)
}

LogFilterer provides access to contract log events using a one-off query or continuous event subscription.

Logs received through a streaming query subscription may have Removed set to true, indicating that the log was reverted due to a chain reorganisation.

type PendingContractCaller

type PendingContractCaller interface {
	PendingCallContract(ctx context.Context, call CallMsg) ([]byte, error)
}

PendingContractCaller can be used to perform calls against the pending state.

type PendingStateEventer

type PendingStateEventer interface {
	SubscribePendingTransactions(ctx context.Context, ch chan<- *types.Transaction) (Subscription, error)
}

A PendingStateEventer provides access to real time notifications about changes to the pending state.

type PendingStateReader

type PendingStateReader interface {
	PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error)
	PendingStorageAt(ctx context.Context, account common.Address, key common.Hash) ([]byte, error)
	PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error)
	PendingNonceAt(ctx context.Context, account common.Address) (uint64, error)
	PendingTransactionCount(ctx context.Context) (uint, error)
}

A PendingStateReader provides access to the pending state, which is the result of all known executable transactions which have not yet been included in the blockchain. It is commonly used to display the result of ’unconfirmed’ actions (e.g. wallet value transfers) initiated by the user. The PendingNonceAt operation is a good way to retrieve the next available transaction nonce for a specific account.

type Subscription

type Subscription interface {
	// Unsubscribe cancels the sending of events to the data channel
	// and closes the error channel.
	Unsubscribe()
	// Err returns the subscription error channel. The error channel receives
	// a value if there is an issue with the subscription (e.g. the network connection
	// delivering the events has been closed). Only one value will ever be sent.
	// The error channel is closed by Unsubscribe.
	Err() <-chan error
}

Subscription represents an event subscription where events are delivered on a data channel.

type SyncProgress

type SyncProgress struct {
	StartingFastBlock uint64 // Snail Block number where sync began
	CurrentFastBlock  uint64 // Current block number where sync is at
	HighestFastBlock  uint64 // Highest alleged block number in the chain

	StartingSnailBlock uint64 // Block number where sync began
	CurrentSnailBlock  uint64 // Current block number where sync is at
	HighestSnailBlock  uint64 // Highest alleged block number in the chain
	PulledStates       uint64 // Number of state trie entries already downloaded
	KnownStates        uint64 // Total number of state trie entries known about
}

SyncProgress gives progress indications when the node is synchronising with the Truechain network.

type TransactionReader

type TransactionReader interface {
	// TransactionByHash checks the pool of pending transactions in addition to the
	// blockchain. The isPending return value indicates whether the transaction has been
	// mined yet. Note that the transaction may not be part of the canonical chain even if
	// it's not pending.
	TransactionByHash(ctx context.Context, txHash common.Hash) (tx *types.Transaction, isPending bool, err error)
	// TransactionReceipt returns the receipt of a mined transaction. Note that the
	// transaction may not be included in the current canonical chain even if a receipt
	// exists.
	TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error)
}

TransactionReader provides access to past transactions and their receipts. Implementations may impose arbitrary restrictions on the transactions and receipts that can be retrieved. Historic transactions may not be available.

Avoid relying on this interface if possible. Contract logs (through the LogFilterer interface) are more reliable and usually safer in the presence of chain reorganisations.

The returned error is NotFound if the requested item does not exist.

type TransactionSender

type TransactionSender interface {
	SendTransaction(ctx context.Context, tx *types.Transaction) error
}

TransactionSender wraps transaction sending. The SendTransaction method injects a signed transaction into the pending transaction pool for execution. If the transaction was a contract creation, the TransactionReceipt method can be used to retrieve the contract address after the transaction has been mined.

The transaction must be signed and have a valid nonce to be included. Consumers of the API can use package accounts to maintain local private keys and need can retrieve the next available nonce using PendingNonceAt.